flake: bump plutarch, fix resulting issues

Collection of things fixed:
- `agora-test`: Fix compile resulting from some changes to hackage.
- `agora-benchmark`: Switched to `plutarch`-style `evalScript`.
- CI: Ported over new flake changes.

This is quite a mess.

agora.cabal

@@ -67,6 +67,7 @@ common lang
     PatternGuards
     PolyKinds
     PostfixOperators
+    QualifiedDo
     RankNTypes
     RelaxedPolyRec
     ScopedTypeVariables
@@ -80,7 +81,6 @@ common lang
     UndecidableInstances
     ViewPatterns
     OverloadedRecordDot
-    QualifiedDo
 
   default-language:   Haskell2010
 
@@ -128,6 +128,7 @@ common test-deps
     , tasty-hunit
     , tasty-quickcheck
     , universe
+    , universe-base
 
 common exe-opts
   ghc-options: -threaded -rtsopts -with-rtsopts=-N -O0
@@ -219,6 +220,7 @@ benchmark agora-bench
     , agora-specs
     , agora-testlib
     , cassava
+    , mtl
     , optparse-applicative
 
 executable agora-scripts